THE K2U POLAR NOMOGRAM: AN INTERACTIVE VISUALIZATION METHOD FOR REAL-TIME ASSESSMENT AND SOURCE DIAGNOSIS OF THREE-PHASE VOLTAGE UNBALANCE
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Abstract
Continuous monitoring of the voltage unbalance factor K2U produces long streams of numbers that answer the regulatory question — is the 2 % normal or 4 % maximum limit of GOST 32144-2013 exceeded? — only after inspection of tables or time-series plots, and say nothing direct about where the unbalance comes from. We describe a polar nomogram in which the radial coordinate is K2U, the angular coordinate is the phase angle φ2 of the negative-sequence voltage component, and the normative limits appear as concentric zone boundaries. A single glance then answers both questions at once: the distance of the operating point from the centre shows the margin to the limits, and the angular sector in which measurements cluster points to the origin of the unbalance. The method is implemented as an interactive web module with live recomputation, a history trail and a drag-to-explore inverse mode, and is illustrated on a simulated telecommunications load profile in which the φ2 cluster correctly identifies the loaded phase.
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